Equation of State of the Transplanckian Dark Energy and the Coincidence Problem

Abstract

Observational evidence suggests that our universe is presently dominated by a dark energy component and undergoing accelerated expansion. We recently introduced a model, motivated by string theory for short-distance physics, for explaining dark energy without appealing to any fine-tuning. The idea of the transplanckian dark energy (TDE) was based on the freeze-out mechanism of the ultralow frequency modes, $\omega (k)$ of very short distances, by the expansion of the background universe, $\omega (k)\le H$. In this paper we address the issue of the stress-energy tensor for the nonlinear short-distance physics and explain the need to modify Einstein equations in this regime. From the modified Einstein equations we then derive the equation of state for the TDE model, which has the distinctive feature of being continually time-dependent. The explanation of the coincidence puzzle relies entirely on the intrinsic time-evolution of the TDE equation of state.

19 pages, 1 eps figures

References in corpus (20)

• Lorentz invariance with an invariant energy scale
• Quantum Gravity: a Progress Report
• A note on inflation and transplanckian physics
• Inflation as a Probe of Short Distance Physics
• Short Distance vs. Long Distance Physics: The Classical Limit of the Minimal Length Uncertainty Relation
• Perturbation spectrum in inflation with cutoff
• Trans-Planckian dispersion and scale-invariance of inflationary perturbations
• Robustness of the inflationary perturbation spectrum to trans-Planckian physics
• Relic Dark energy from Trans-Planckian Regime
• On Signatures of Short Distance Physics in the Cosmic Microwave Background
• Cosmological perturbations and short distance physics from Noncommutative Geometry
• Current constraints on the dark energy equation of state
• Einstein Gravity as an emergent phenomenon?
• The stress-energy tensor for trans-Planckian cosmology
• A late-time transition in the cosmic dark energy?
• The Corley-Jacobson dispersion relation and trans-Planckian inflation
• Possible astrophysical probes of quantum gravity
• Modified Dispersion Relations from Closed Strings in Toroidal Cosmology
• On dispersion relations and the statistical mechanics of Hawking radiation
• The Asymptotic Structure of Space-Time

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• What Can WMAP Tell Us About The Very Early Universe? New Physics as an Explanation of Suppressed Large Scale Power and Running Spectral Index
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• CMB quadrupole suppression: II. The early fast roll stage
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• When Did Cosmic Acceleration Start ?
• Observational Constraints on Accelerating Brane Cosmology with Exchange between the Bulk and Brane
• Do We Have Evidence for New Physics in the Sky?
• Duality extended Chaplygin cosmologies with a big rip
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• A Note on Trans-Planckian Tail Effects